Fire alarm signal station



Feb. 15, 1955 M. LEVY 2,702,330

FIRE ALARM SIGNAL STATION Original Filed May 15, 1952 A TTOEZVE'Y United States Patent 2,702,330 FIRE ALARM SIGNAL STATION Morris Levy, Philadelphia, Pa.

Application May 25, 1953, Serial No. 356,948

3 Claims. (Cl. 200-142) My invention relates to a new and useful fire alarm signal station and one of the objects thereof is to produce a signal station including an electric switch normally retained in an open condition by a frangible panel to be fractured by means on the exterior of the station, which means is releasable manually or by the presence of abnormal heat in the vicinity of the location of said station to produce an audible or visible alarm.

This application is a division from my application for patent filed May 13, 1952, Serial No. 287,640.

One object of this invention is to provide a fire alarm signal station comprising a body having a recess in which a switch is assembled and normally held in open condition by a frangible panel to be broken by an automatic hammer on the exterior of said body, said hammer being generally maintained in an inoperative condition by a fusible element which may be released manually or melted by the presence of abnormal heat to release the hammer and by automatic action to break the panel whereby the switch can close to cause operation of an alarm.

Another object of the invention is to provide a fire alarm signal station including a switch normally maintained in an open position by a frangible panel which may be broken by a spring actuated hammer directly or indirectly held in a neutral or cocked position by a fusible element, said hammer being releasable manually or when the fusible element melts due to the presence of abnormal heat.

A further object of the invention is to provide a spring actuated swinging hammer normally maintained in the neutral position by a fusible link which when manually detached or melted by abnormal heat will release the hammer to break the panel whereby the switch may be closed.

With the above and other objects in view this invention consists of the details of construction and combination of elements hereinafter set forth and then designated by the claims.

In order that those skilled in the art to which this invention appertains may understand how to make and use the same I will describe its construction in detail referring by numerals to the accompanying drawing forming a part hereof, in which:

Fig. 1 is a perspective view of a fire alarm signal station constructed in accordance with my invention.

Fig. 2 is a section on the line 2-2 of Fig. 1 with some of the parts shown in elevation.

In carrying out my invention as herein embodied represents the body of the station, preferably produced from an appropriate dielectric material, having a chamber 11 in which is mounted the terminal member 12 held in place by a fastening device 13, such as a screw or bolt, and through which said terminal member is electrically connected with one side of an electric circuit including an audible or visible alarm device (not shown).

Attached to said terminal member 12 is a movable spring contact 14, the free end of which underlies a stationary contact mounted in the chamber 11 and held in place by a fastening device 16, such as a screw or bolt, and through which said stationary contact is electrically connected with the other side of the electric circuit including the alarm device mentioned above.

The free end of the movable spring contact 14 is reciprocatingly positioned beneath the stationary contact member 15 within a recess in the bottom of the chamber 11 to accommodate the movements of said free end of said movable spring contact. Said movable contact is fashioned to provide an outwardly projecting knee 17 for a purpose to be described below.

The outer open end of the chamber 11 is covered by a 2,702,330 Patented Feb. 15, 1955 frangible panel 18, set in a rabbet 19 surrounding said open end of the chamber and held in place by fastening devices 20, such as screws. Said panel engages the knee 17 of the movable spring contact to depress and normally hold it out of engagement with its companion stationary contact 15 whereby the switch is normally open until such time as the panel 18 is broken.

To break the panel 18 I have provided a spring operated hammer 21 including a head 22 mounted on a shank 23 having a right angled journal 24 mounted in bearings 25. A coil spring 26 surrounds the journal 24 and has one end fixed to the body and the other end connected with the hammer in a manner to swing the head 22 in the arc of a circle towards the panel 18 so as to strike and break the latter.

The hammer normally is retained in a retracted position, as shown by full lines in Fig. 2, by the fusible element 27 having one end connected to said hammer and the other end temporarily attached to the body 10 of the station by a detachable fastening device 28, such as a headed pin. For purposes of illustration the fusible element is shown as comprised of two overlapping plates 29 and 30 joined together by a suitable solder between them or along their coacting edges. In practice, one plate is mounted on the hammer shank 23 and the fastening device 28 is projected through a hole in the companion plate and into the station body.

In operation when heat due to a fire in the vicinity of the station melts the fusible element the hammer will be released and then propelled by the spring 26 to cause the head to strike and break the panel 18. This, in turn, will release the movable spring contact 15 and close the switch for producing an alarm. If the fire is not close enough to the station to melt the fusible element but a person is present the fastening device 28 can be withdrawn manually which will also release the hammer, along with said fusible element, and allow the hammer to be propelled by its spring for striking and breaking the panel for the purpose of producing an alarm.

Of course I do not wish to be limited to the exact details of construction herein shown and described as these may be varied within the scope of the appended claims without departing from the spirit of my invention.

Having described my invention what I claim as new and useful is:

l. A fire alarm signal station comprising a body provided with a chamber having a frangible panel disposed across the open outer end thereof, an electric switch located in said chamber and including a movable spring contact the depression of which opens the switch and coacting with said panel to normally be maintained in the depressed position, a spring actuated hammer for breaking said panel, and fusible means secured to said hammer and detachably connected to the body for holding said hammer retracted which when said fusible means is melted or manually detached will liberate the hammer to break the panel and release the movable contact to close the switch.

2. The fire alarm signal station according to claim 1 wherein the hammer is of the swinging type to travel in the arc of a circle.

3. A fire alarm signal station comprising a body having a chamber with an open front, an electric switch located in said chamber and including a movable contact constantly urged towards said open front and having a portion projecting outside of the chamber, a frangible panel disposed across the open front of said chamber and engaging the projecting portion of the movable contact to depress the latter for opening the switch, a spring actuated hammer swingingly mounted on the casing, and fusible means secured to said hammer and detachably connected with said casing to normally maintain the hammer in a retracted position, the melting or manual detachment of the fusible means liberating the hammer whereby it will break the panel to release the movable member and thereby close the switch.

References Cited in the file of this patent UNITED STATES PATENTS 2,570,823 Levy Oct. 9, 1951 

